Machine and method of knitting a reinforced tubular cover over a flexible hose or the like



Al BAUM M? J. GRECZIN ETAL COVER OVER A FLEXIBLE HOSE OR THE LIKE Filed Jan. 2, 1968 .V Mii gis!! le l FIG.

Aug. 26, 1969 MACHINE AND METHOD OF KNITTING A REINFORCED TUBULAR United States Patent O MACHINE AND METHOD OF KNITTING A REIN- FORCED TUBULAR COVER OVER A FLEXIBLE HOSE OR THE LIKE John Greczin and Roy D. Faigenbaum, both of 7312 School Lane, Melrose Park, Philadelphia, Pa. 19126 Filed Jan. 2, 1968, Ser. No. 695,051 Int. Cl. D04b 9/06 U.S. Cl. 66-9 3 Claims ABSTRACT F THE DISCLOSURE A tubular fabric formed of alternate needle wales and intermediate, un-knit connecting wales and lay-in, or wraparound yarns which pass in f-ront of the loops of the needle wales and behind the loop of the connecting yarns.

THE INVENTION The principal features of the invention reside in using twice as many needles as knitting cams, in spacing the cams with flats so as to knit on alternate wales only, and in rotating the cams in one direction -and rotating the wrap-around yarns in the opposite direction.

The invention is carried out on a multifeed machine which includes a single needle cylinder, one set of needles, one set of knitting cams and 'a rotary spider carrying the wrap-around yarns. Since such machines are well known and form no part of this invention, they are not shown, nor described, and for details of their construction and operation, reference may be had to Larkin Patent No. 2,201,905 and the patents cited therein, and other patents and publications which are available in the files of Group 364 of the IU.S. Patent Oiiice. Therefore, only the knitting needles, the knitting cams and the tubular fabric produced according to this invention are shown in the details.

The type of tubular fabric with which this invention is concerned is exemplified by Larkin Patent No. 2,032, 993; Greczin Patent No. 2,870,619, and other patents which are also available in the Patent Oflice, Greczin Patent No. 2,257,828.

IN THE DRAWINGS FIG. 1 is a developed view diagrammatically showing the needles and the knitting cams which operate the needles.

FIG. 2 is a view of the Ifabric produced according to this invention.

FIG 2a is an enlargement of a portion of the fabric shown in FIG. 2.

FIG. 3 is a diagrammatic top plan view showing the needle cylinder, the yarn feeds and the bobbins which supply the wrap-around yarns.

In carrying out the invention, we use a needle cylinder having a predetermined number of needles, and a cam ring R having half as many knitting cam lobes as there are needles, said cam lobes alternating with depressed ats which prevent the needles from knitting until each needle has traversed a at between adjacent lobes. In the preferred embodiment illustrated, there lare eight needles N1 to N8 and four knitting cam lobes C1 to C4 which are separated by depressed flats or lands L1 and L4 on which the needles do not knit. The cam ring R rotates in the Ffice direction of the arrows in FIG. 1 or in counter-clockwise direction as viewed in FIG. 3.

As shown in FIG. 3, there are four yarn feeds F1 to F4 which supply knitting yarns Y1 and Y4 to the needles at knitting stations S1, S3, S5 and S7; four bobbins B1 to B4 which supply wrap-around yarns W1 to W4. The bobbins B1 to B4 are carried by a conventional spider which forms no part of the invention and is, therefore, not shown, nor described. It is enough to note that spider and the bobbins carried thereby rotate in clockwise direction as viewed in FIG. 3.

THE OPERATION IS AS FOLLOWS As the cam ring R rotates in counter-clockwise direction, the needles are successively raised to the upper, yarnengaging, or knitting stations S1, S3, S5 and S7, and are depressed onto at lands L1 to L4. As the needles move down, they form the loops of needle wales 10, 12, 14, 16, 18, 20, 24 and 26. As the needles traverse the intervening flats, they miss the yarn and instead of loops, the connecting wales 11, 13, 15, 17, 19, 21 and 23 (for want of a better word), are formed. In the meantime, the wraparound yarns are laid in front of the loops and the connecting wales. FIGS. 2 and 2a. In this way, the wraparound yarns are held in position by the connecting wales on either side of each needle Wale. In other words, the lay-in yarns are engaged at intervals which are a function of the width of the needle wale loops. Since the loops are very narrow, the yarn will not have any perceptible movement relative to the loops of the needle wales or to the overlay or cross-over yarns of the connecting wales.

Synthetic yarns of the type used in making a covering of this kind have an enormous tensile strength as long as they are tensioned in the direction of their length only and they lose a substantial portion of their strength when they lare knotted or sha-rply bent. In the construction illustrated, the wrap-around yarns form helices which spiral about the hose being covered. By this arrangement the wrap yarns retain their original strength and thus they are able to coniine and prevent bulging of a tube under pressures which would blister or rupture a hose covered with the knitted fabric of FIG. 2 from which the unknitted wrap-around yarns are omitted.

Another feature of this invention is the rotation of the wrap-yarns bobbins in a direction opposite to the direction of the knitting so as to oppose the tendency of the covered hose to twist as it would if the wrap-yarns and the knitting proceeded in the same direction.

What we claim is:

1. In a circular knitting machine of the type which includes a single needle cylinder and has a number of yarn feed stations,

a predetermined number of needles,

a rotary cam ring having a number of knitting cams equal to one-half of the number of needles, and having depressed ats alternating with said cams whereby needle wales are formed which alternate with connecting wales, and

supply means for feeding wrap yarns at said stations,

said means being rotated about the axis of said cylinder in a direction opposite to the direction of rotation of said cam ring.

2. The method of knitting a tubular cover formed of loops and of wrap yarn, over a flexible hose or the like,

said method including the step of rotating the knitting cams in one direction and rotating the wrap yarn in the opposite direction, and the step of withdrawing the knit fabric upwardly of the knitting machine.

3. The method of knitting a tubular cover formed of loops and wrap yarn, said method including the step of knitting needle wales separated by connecting wales and laying the wrap yarn over said wales and beneath said connecting wales.

References Cited UNITED STATES PATENTS Ford 66-9 Larkin 66-190 Stover 66-9 Stover 66--9 Dauphinais 66-9 XR Greczin 66-190 Greczin 66-9 Greczin 66-9 XR U.S. Cl. X.R. 

